What Ultima said^^. I watched half of it yesterday and thought it was pretty good but just not a huge CF fan.

1: Do I have to know anything about the franchise going in to follow what's going on?

2: If I DO know something, is it going to piss all over it?

3: Is there any nudity in it (this is a big one I need a firm yes/no answer. My employer's will ignore me watching it on a slow night at work to stay awake if there's no nudity, but if there is I'd be fired for it. ) ?

1: How well do you have to know the franchise going in to get what's going on?

2: If you DO know the franchise going in does it give you the middle finger for doing so?

3: Is there any nudity (I know Ultraman is traditionally targeted in such a way as to not have that, but my understandings are that there have been at least 1/2 series in the past that break that rule. Since i'll be watching when it's slow at work, I don't want to risk it with out a heads up in advance.).

4: Is it outright crap, or is it at least entertaining/enjoyable?

1: No. It's all pretty well explained, but there are also huge differences in the history to the show I grew up watching. So in fact, you might be better off not knowing anything.
2: Liberties were taken and changes made.
3: not in the first 2 episodes
4: Not my taste (see major liberties taken) but it isn't utterly terrible.

There were something like 9 Ultramen, be I only ever got to see the first one.
Originally, The Guy had to push the button on his widget to turn into the giant kaiju fighter. Because he was bonded to the human, Ultraman had a limited timespan/power supply, and there was a flashing light on his chest to warn him when he only had one minute left. The original actor in the Ultraman scuba suit (painted silver and red) was a martial artist, and used actual art poses for his FX power attacks.
Now UltraMan seems more like an Iron Man knock off. Maybe this is addressed/resolved in later episodes.

They did at least keep a nod towards the time limit by having him enter a powered up mode he can only sustain for a few minutes.

The similarities to Iron Man are there, but the wearers are clearly superhuman to begin with. The suit provides a lot of weaponry and apparently actual flight as opposed to just jumping around, presumably some protection as well. He definitely does a lot more hand to hand than any iteration of Iron Man.